'72 K5 - Greg's @MightAsWellK5 Build

[Greg72]

It looks like the ORIs are emulsions in the upper and lower chambers. That reservoir you linked just adds more volume(a larger volume will have less rate of change over the stroke of the shaft because you are changing volume less percentage over the travel). This rezi looks better...

http://shop.oristruts.com/products/high-capacity-reservoir

However, neither of them seperate the nitrogen from the oil, so some fade may be experienced when they get hot.

Anyway, the main point I was trying to say is, you don't want to have to take the shock apart to pass it through the hole during installation to the rig if there is a hose sticking out the side of it, so be aware of that.

I think I'm going to be fine as far as installation goes. If you look at the images from my front strut mounts and the orientation of the Schrader valve you can see that it's a straightforward install.... the rear design is just a mirror-image of my front design (valve faces the rear bumper instead).

At this point, my strategy is just to install the bare struts that I have now (no resi) and see how they feel... if I feel like I'm losing ride quality because of excessive vehicle weight (and resulting high nitrogen PSI to achieve ride height)

I will add a set of those cheaper resis and see what that does.... I like that they appear to be 100% bolt-on and I don't have to disassemble the struts or mess around with oil levels. Just screw them onto the existing Schrader valves, repressurize and GO!!!

The "Fixed" style resi is going to be problematic, since it will require me to change the upper mounts at each corner. I also don't like that I have to pull the struts apart to rework them. The ride quality is going to have to be REALLY bad to justify the effort and expense of doing that retrofit.



-G

 

[MNorby]

after my ST died after the race and I sent my old rears in to be upgraded to STX models, etc I asked about the piggyback res and Mark the owner flat told me not to spend the money on them for my application of rock crawler and some u4 type racing. He said they were designed for heavy mega trucks and stupid air.

 

[Greg72]

after my ST died after the race and I sent my old rears in to be upgraded to STX models, etc I asked about the piggyback res and Mark the owner flat told me not to spend the money on them for my application of rock crawler and some u4 type racing. He said they were designed for heavy mega trucks and stupid air.

Thanks for that info.

I'm glad I don't have to worry about reworking my mounts for a fixed resi.... I've got no problem adding the smaller nitrogen ones if needed, that's a pretty simple change.



TUESDAY NIGHT UPDATE:


Just a few incremental steps forward last night.

I tacked the PS mount in place to lock everything in, and stabbed the ORI back into place to see how it looked.

It's sort of surprising how little of the strut you actually "see" now that it's got some structure around it.

A neat trick that I'm using again is to leave the thick-walled DOM slugs unwelded during the initial fitup of parts. This allows me to slide the strut from side-to-side by maybe 3/4" and fine-tune it's position laterally in the mount depending on where the clearance issues are in other places. I put one tack weld on it last night.... but in a spot that will be easy to grind off if needed. During the rear suspension cycling tests it may need a slight tweak... and it's nice to still have a small amount of flexibility. (That's the reason why I left those DOM slugs a bit on the long side as well. I'll cut them down to final length once I'm 100% sure of everything)

The driver's side got tacked into position as well, and I did the final fitting of the underside plate that ties the two horizontal bars together....basically just doing the two crescent-shaped notches that allow it to fit snugly between the tubes. It's not welded in yet since I still need to drill the speed hole in the center of it.

Working on the driver's side is a bit tougher also because there is a factory bedside in the way!

The "sneaker view" angle!!! I risked life and limb to bring you this one.... perched above the rollcage with one foot bracing myself and trying not to fall through the xfercase area as I leaned precariously close to my own CoG to get the shot "just right"!!!

Ignore the oddball, mismatched floor panels for the time being.... instead focus on the fact that the bedfloor is almost completely open and useable for storage, rear seat or whatever. (maybe even sheet plywood!)

In any case, tonight I'll try to get the driver's side mount tacked completely into position and then maybe mount the other strut. Then I can pull the rear tires/wheels and start looking at how I'm going to build the lower strut mount towers and get them mounted to the axle....




-G

 

[Z71paramedic]

Looking good!

 

[folkenheath]

Can you cycle it first to make sure you don't hit the strut with the tire at full articulation? I would do that before you start making the lower mounts too. I see your notches in the frame for the upper link axle mount, so you can see about how far the tire will travel laterally, which may be multiplied by the height of the tire from the axle vs the height of the link mount.

That's going to be a big step when you have all 4 struts done!

 

[Greg72]

Can you cycle it first to make sure you don't hit the strut with the tire at full articulation? I would do that before you start making the lower mounts too. I see your notches in the frame for the upper link axle mount, so you can see about how far the tire will travel laterally, which may be multiplied by the height of the tire from the axle vs the height of the link mount.

Thats going to be a big step when you have all 4 struts done!

Heath,

Keep in mind, the suspension in these photos is already at "full stuff" in both front and rear. I know that when I drop a single rear wheel the strut will move laterally.... I'm just not sure HOW much.

Most "real" builders I see design everything with the suspension fully stuffed since it really does seem to be the worst-case-scenario for interferences....

-G

 

[folkenheath]

I realize that, but it's not worse case scenario for that interference, when you drop one side all the way the top of the tire will move in. So leave one tire on and droop the other side all the way, then swap the tire and do the opposite. Although it should be symmetrical in the back. Now that you have the struts loosely mocked up its the perfect time to cycle it before you build the rest of the brackets. This will also tell you if you need to clearance the strut hole in the plate anywhere as well.

Hopefully it doesn't hit, but if it does you don't want to find out later. And yes many builders design it at full stuff (I prefer ride height so it's easier to set pinion angle, cycle to full stuff, full droop, articulate, and steer all without moving the chassis), but that doesn't mean they don't cycle it before all the brackets are finalized, that would be a big mistake.

 

[Greg72]

I'll definitely pull the DS wheel/tire and do some droop tests....

... I just hope I don't have to chop out any concrete to get to full-droop!!


-G

 

[chevyfumes]

Actually looks like you're making good progress now, maybe I'm just excited to see more pics but it's getting there. I'm sure you'll have it finished just in time to tear it all apart to start on version 4.2

 

[blazinzuk]

I am with Heath. I would cycle it now. Before the lower mounts are built. Worst case scenario all you will have to do is make the holes in the upper shock mount base plate oval instead of a circle.

I am sure you have a pretty good idea of where the lower mounts need to go.

 

[Greg72]

I am with Heath. I would cycle it now. Before the lower mounts are built. Worst case scenario all you will have to do is make the holes in the upper shock mount base plate oval instead of a circle.

I am sure you have a pretty good idea of where the lower mounts need to go.

OK... I'll give that a shot. Maybe tonight?

Ovaling-out the upper plates will still be pretty simple. I decided to cut off those spot welds and do all of the finish-welding of those upper mount "pyramids" on the bench anyway... it will be a lot simpler to get in-position for welding that way.


-G

 

[bp71k5]

Looking fairly awesome Greg.

 

[76zimmer]

A simple but maybe not so quick way of strengthening those holes would be to weld a thin (3/16 or 1/4" tall) piece of DOM the size of the hole in effect making it like a dimple die hole
Great work Greg....Im amazed at the patience and dedication

 

[cybrfire]

Mounts look great Greg.

Any concern the inner tube is going to flex up and down?

 

[Greg72]

Mounts look great Greg.

Any concern the inner tube is going to flex up and down?

Thanks Kert!

Your opinion means a lot to me.

I think the flexing will be minimal, now that I've got the bars locked together and have that triangulated plate going the the angled down bar (leading edge). I'm pretty sure I'll do a similar plate on the trailing edge also for some extra margin...

I did some flex tests last night. I'll post photos in a couple of hours once I get them organized.


-G

 

[jekquistk5]

Speaking of inner tubes, whats your plan for sealing the hole where the strut passes through the fender? I was thinking a tractor inner tube cut and stretched may actually work well. Either that or thick rubber matt from mcmaster car with pie cut slices. I know its a bit away but something to think about.

 

[Greg72]

2014.12.11 - UPDATE! - CHOPPING CONCRETE...!!!!


Yep... it happened.

I tried to do the "droop test" to see where how well the upper hangers would do, and I hit the floor with the drooping-side rotor!! It's my own fault for getting greedy and buying the longest travel strut I could afford!!!

Here's a shot as I tried to get "max articulation" out of the rear axle...

I could only get to about 12" of chrome showing on the drivers side strut before the rotor/caliper hit the floor, so instead of "chopping concrete" I decided to be a little smarter and just unbolt the complete portal box assembly (weighing about 80Lbs) and get the necessary clearance THAT way instead....

That allowed me to get a few more inches of droop and it looked more like this.....

... but it still wasn't at 16" yet. I took a careful look around and realized that the next interference point was actually the strut on the passenger side. As predicted, the strut body had moved laterally and was contacting the through-hole which was hanging up the travel on the opposite side.

I had a sneaking suspicion that my perfectly round 5" through hole was someday going to be an OVAL... So I made a new mark 1" further back from the original hole and scribed the curve. (Now it's a 5" wide x 6" long oval) I didn't bother to do all the clearancing yet.. just enough to resolve the immediate interference issue.

It worked great! By standing on the drivers side of the axle, I could force it down to the full 16" of droop. The upper link mount on the passenger side was starting to hit the framerail (as expected) so it was adding some resistance to my test. I think the fact that I still had a tire on one side was also adding some "stored energy" and the tire was fighting me also. I think I'll probably pull that wheel/tire off over the weekend and just ratchetstrap that side all the way up against the bumpstop instead.


-G

 

[dabomb6608]

mmmmMMMMMMMMMMmmmmm.........fllleeeexxxxxxx


In all seriousness. Looking good! Might be a dumb question. But what is that lower strut bolt/mount made of? Seems like it will see a lot of load with it being such a long extension from the link mount before the strut mounts to it. Will there be a lot of leverage being that far offset?

 

[folkenheath]

2014.12.11 - UPDATE! - CHOPPING CONCRETE...!!!!

That allowed me to get a few more inches of droop and it looked more like this.....

-G

Was the tire rubbing the strut shaft? Can you move the bottom of the strut in a little? Or the top? Or both? And why is the passenger side still extended some, doesn't look completely compressed? I think you have a major interference there with the tire happening.

 

[Greg72]

Was the tire rubbing the strut shaft? Can you move the bottom of the strut in a little? Or the top? Or both? And why is the passenger side still extended some, doesn't look completely compressed? I think you have a major interference there with the tire happening.

I don't think it was rubbing, but you're right... it's getting REALLY close. I'll try jacking that side with the tire still mounted to see if I can get to 5/8" of chrome showing. That's the "full bump" for ORIs.... if the tire rubs, I'll need to trim the sidewalls for clearance.

I can certainly play games with moving the lower mount a little toward the center of the truck, but the struts will start to look a little bit like this at ride height:

\ ............/


That may not be the end of the world... 5* of angularity is only a small fractional change in dampening rate. It looks a bit odd but the struts are going to be almost completely hidden behind sheetmetal and rubber weatherproofing boots that you'd never really see it.

I can also add a bit more WMS to the truck for clearance too. I figure another .500" per side is pretty subtle and that might give me just enough clearance in these extreme articulation situations.

About the only thing I don't want to do at this point is move the upper mount more inboard... and that's only because of the amount of rework that it would involve to my just-built bracketry. I'd hate to scrap them when they still have that "new car smell"!!!


-G